Ten Black Hawk helicopters took a bubble bath Monday at the Oklahoma Army National Guard aviation facility in Tulsa.

A fire suppression system released foam that filled a hangar and spread to the area outside of it, Col. Max Moss told USA TODAY Network.

The system was installed in the building recently by SimplexGrinnell, a company that makes fire protection systems, according to Moss. A representative from the company was at the facility performing a routine system check and unintentionally triggered the foam, Moss said.

Photos released by the Army National Guard show the helicopters sitting in what looks like a sea of white bubbles.

The hangar was cleaned up within a few hours, according to Moss, and the helicopters were mostly unharmed.

"Six of them have been deemed to be fully operational, and we're continuing to perform maintenance over the next few days on the other four," he said, adding that they should be ready in a short amount of time.

This kind of accidental foam release is an "extremely rare occurrence," Chris Woodcock, a spokesperson for SimplexGrinnell told USA TODAY Network. However, freelance aviation reporter David Cenciotti has documented a few other foam-filled hangars in recent years on his blog, "The Aviationist."

"The takeaway from this is that the system itself is an effective system when it's deployed," Moss said. "Obviously we don't want it to accidentally deploy, but the system itself is very effective in terms of its ability to protect our multimillion-dollar helicopters."

There is a helicopter sitting in the middle of this safety foam.(Photo: Oklahoma Army National Guard)